The objective of this project is to test the hypothesis that artificial flavors and colors in food cause hyperactive behavior disorders in children. This proposal seeks to identify children commonly referred to as hyperkinetic or minimal brain dysfunctioned; to determine whether they react positively to a special diet which eliminates suspected harmful substances and adversely to diets containing such substances; to investigate the genetic, physiological and biochemical characteristics of responders to the special diet; and to establish specific food substances which might cause them to develop adverse behavioral functioning. Standardized selection procedures will be used to define the population. History and examination procedures will seek to determine whether the children have a genetic background, adverse perinatal complications or environmental stress that might sensitize them to food additives. Tests of autonomic function and cortical evoked response will be obtained so as to aid in further identifying subgroups of responders and nonresponders. A test to measure erythrocyte response to challenge with specific food substances will be employed as a further measure to identify possible allergic mechanisms responsible for dietary effects. Methods of measurement will include the use of standardized rating scales for parent and teacher, quantitative measures of motor activity and attention.